1. Field of the Invention
The present invention relates to apparatus and a method for generating call pattern data for scheduling connections between a number of sites connected to a communication network. The connections will include voice type telephone calls as well as machine-to-machine calls and voice-to-machine calls, all of which will be referred to throughout the remainder of the description using the term xe2x80x9ccallsxe2x80x9d.
2. Related Art
In networking operations it is often desirable to simulate the day to day running of the network to allow the network operators to check that the network is functioning correctly. One example of where this is particularly important is in the case of public switched telephone networks (PSTN) in which it is desirable to generate a series of calls between different sites on the network to enable the network operator to check the billing procedure of the network. By having a prior knowledge of the calls that are made, the operator can compare the charges the system assigns to each site with the theoretical charge that should be made.
Currently the only method of generating such calls is to assign individual calls on a call by call basis to individual stations. However this does not simulate the normal running of the PSTN for three main reasons. Firstly, the network will generally be functioning under a far higher call load than the operator is able to generate. Secondly, calls over a network will normally occur in a random sequence which it is impossible for the operator to simulate. Thirdly, the calls will usually be spread out between numerous stations on the network and not between the few stations that the operator is able to assign calls to.
According to a first aspect of the present invention, we provide a method of generating call pattern data for scheduling calls between a number of sites connected to a communication network, where the call pattern data defines instructions for a number of sites to make a number of connections across the network to other sites over a predetermined period, comprising the steps of creating a list of calls to be scheduled, assigning in turn each of the calls to a source site selected from a list of sites and selecting a destination site for each call from the list of sites, the source site and destination site being selected to satisfy a number of call constraint criteria associated with each call, generating and storing the call pattern data on a computer storage medium for subsequent download.
According to a second aspect of the invention, we provide apparatus for generating call pattern data for scheduling calls between a number of sites connected to a first communications network, where the call pattern data defines instructions for a number of sites to make a number of connections across the first communications network to other sites over a predetermined period, the apparatus comprising a sequencer for creating a list of calls to be scheduled, wherein the sequencer comprises a storage medium for storing data defining a list of sites connected to the first communications network, a processor for assigning in turn each of the calls on the list to a source site selected from the list of sites and selecting a destination site for each call from the list of sites, the source site and destination site being selected to satisfy a number of call constraint criteria associated with each call, and an input device for inputting data defining the call constraint criteria into the storage medium, and wherein the call pattern data generated by the processor is stored on the storage medium.
The present invention provides both a method and apparatus for generating call pattern data for scheduling calls between a number of sites connected to a communication network. The calls scheduled according to the call pattern data must satisfy a number of call constraint criteria that may be determined by the operator of the system. This allows the operator to specify the nature of the calls that are made without having to specify details of the calls on an individual basis. As a result the operator can quickly and easily generate data that can be used to control calls over a network to simulate the day to day operation of a network. By allowing the operator to set the call levels conditions of normal load, underload or overload may be simulated.
Typically the call constraint criteria includes an indication of the total number of calls to be made during the predetermined period although this may be preset.
Preferably the call constraint criteria includes an indication of the type of call to be made, the types of call including simple chargeable and simple non-chargeable, although any type of suitable call such as a freephone call, BT charge card call, mobile phone call or phone conference call may be included.
Whilst the communications network may be a single contiguous network, preferably the communications network is divided into a number of zones with the sites being distributed between different zones and the call constraint criteria including an indication of the zone from which the calls are to be made. In such a case information concerning which zones the sites may be located in, so as to be suitable for receiving the defined calls, is also provided. This will depend upon the charge band under which the call up to be made i.e. local, regional or national.
Preferably the call constraint criteria also indicates the rate at which calls are to be charged, although this could be left undetermined. This will usually depend on factors such as the time of day at which the calls are made and the destination of the call.
Typically the call constraint criteria further includes the requirement that the variation in the utilisation of each site over the predetermined period is minimised. This is preferable as it results in an even spread in usage over all the sites on the network. However, it could be foreseen that in some circumstances an uneven distribution of usage may be advantageous in modelling the operation of a real network.
Typically the sequencer has a display, for displaying the call constraint criteria stored in the storage medium.
Preferably the apparatus also has a secondary storage means connected to a second network, with the sequencer connected to the second network so it can download the call pattern data to the secondary storage medium over the second network. This prevents the storage medium of the sequencer become overloaded.
According to a third aspect of the invention, we provide a method of generating calls between a number of sites of a communications network to simulate the day to day running of the network, the method comprising generating call pattern data according to the first aspect of the invention, downloading the call pattern data to the number of sites and causing each to respond to the call pattern data to make the calls defined therein.
According to a fourth aspect of the invention, we provide a method of verifying a call charging system of a communications network, the method comprising generating calls between a number of sites of the communications network according to the third aspect of the invention, generating a theoretical charge for the calls, defined for each site, from the call pattern data and comparing the charges assigned to each site by the call charging system to the theoretical charge generated for each site.
According to a fifth aspect of the present invention, we provide apparatus for generating calls between a number of sites of a communications network to simulate the day to day running of the network, the apparatus comprising apparatus according to the second aspect of the invention for generating call pattern data, the apparatus further comprising a controller connected to the second network and to the first network, wherein the controller comprises a controller storage medium and a controller processor, the controller processor being adapted to download the call pattern data, from the secondary storage medium, over the second network, to the controller storage medium and then download the call pattern data from the controller storage medium, over the first network, to the number of sites and wherein the number of sites respond to the call pattern data to make the calls defined therein.
According to a sixth aspect of the present invention, we provide apparatus for verifying a call charging system of a communications network, the apparatus comprising apparatus according to the fifth aspect of the invention for generating calls between a number of sites of the first communications network, a call charging system connected to the first network for assigning a charge to the calls made by each site, and calculation means for downloading results data generated by each site and stored in the controller storage medium, generating a theoretical charge for the calls for each site in accordance with the results data, downloading the charges assigned to each site from the call charging system and comparing the charges assigned to each site with the theoretical charge generated for each site.
These methods and sets of apparatus allow network operators to simulate the day to day operation of a network and consequently check the call charging systems that the network utilises to bill the various sites. It will be apparent to a person skilled in the art that the system will also be useful for testing the integrity and operation of the network under conditions of varying load.
Preferably the communications network is a public switched telephone network, although it will be realised that any network over which sites are able to communicate would be suitable for use with the apparatus and method of the present invention.